Department of Ophthalmology, Christian-Albrechts-University of Kiel, University Medical Center, Kiel, Germany.
Friedrich-Alexander-University Erlangen-Nürnberg, Nürnberg, Germany.
BMC Ophthalmol. 2021 Nov 30;21(1):412. doi: 10.1186/s12886-021-02188-8.
Selective Retina Therapy (SRT), a photodisruptive micropulsed laser modality that selectively destroys RPE cells followed by regeneration, and Thermal Stimulation of the Retina (TSR), a stimulative photothermal continuous wave laser modality that leads to an instant sublethal temperature increase in RPE cells, have shown therapeutic effects on Age-related Macular Degeneration (AMD) in mice. We investigate the differences between both laser modalities concerning RPE regeneration.
For PCR array, 6 eyes of murine AMD models, apolipoprotein E and nuclear factor erythroid-derived 2- like 2 knock out mice respectively, were treated by neuroretina-sparing TSR or SRT. Untreated litter mates were controls. Eyes were enucleated either 1 or 7 days after laser treatment. For morphological analysis, porcine RPE/choroid organ cultures underwent the same laser treatment and were examined by calcein vitality staining 1 h and 1, 3 or 5 days after irradiation.
TSR did not induce the expression of cell-mediators connected to cell death. SRT induced necrosis associated cytokines as well as inflammation 1 but not 7 days after treatment. Morphologically, 1 h after TSR, there was no cell damage. One and 3 days after TSR, dense chromatin and cell destruction of single cells was seen. Five days after TSR, there were signs of migration and proliferation. In contrast, 1 h after SRT a defined necrotic area within the laser spot was seen. This lesion was closed over days by migration and proliferation of adjacent cells.
SRT induces RPE cell death, followed by regeneration within a few days. It is accompanied by necrosis induced inflammation, RPE proliferation and migration. TSR does not induce immediate RPE cell death; however, migration and mitosis can be seen a few days after laser irradiation, not accompanied by necrosis-associated inflammation. Both might be a therapeutic option for the treatment of AMD.
选择性视网膜治疗（SRT）是一种光破坏微脉冲激光模式，它选择性地破坏 RPE 细胞，然后进行再生；热视网膜刺激（TSR）是一种刺激性光热连续波激光模式，导致 RPE 细胞立即发生亚致死温度升高。这些方法在小鼠的年龄相关性黄斑变性（AMD）中显示出了治疗效果。我们研究了这两种激光模式在 RPE 再生方面的差异。
对于 PCR 阵列，使用神经视网膜保留 TSR 或 SRT 分别治疗载脂蛋白 E 和核因子红细胞衍生 2 样 2 敲除小鼠的 AMD 模型的 6 只眼睛。未治疗的同窝仔鼠作为对照。激光治疗后 1 天或 7 天眼球被摘出。对于形态分析，猪 RPE/脉络膜器官培养物接受相同的激光处理，并在照射后 1 小时、1 天、3 天或 5 天进行 calcein 活力染色检查。
TSR 没有诱导与细胞死亡相关的细胞介质的表达。SRT 在治疗后 1 天而非 7 天诱导了坏死相关细胞因子和炎症。形态学上，TSR 后 1 小时没有细胞损伤。TSR 后 1 天和 3 天，单个细胞出现致密染色质和细胞破坏。TSR 后 5 天，有迁移和增殖的迹象。相比之下，SRT 后 1 小时在激光点内可见一个明确的坏死区。这个病变在几天内通过相邻细胞的迁移和增殖来封闭。
SRT 诱导 RPE 细胞死亡，随后在几天内再生。它伴随着由坏死引起的炎症、RPE 增殖和迁移。TSR 不会立即引起 RPE 细胞死亡；然而，几天后可以看到迁移和有丝分裂，没有伴随坏死相关的炎症。这两种方法可能是 AMD 治疗的一种选择。
